detoxifying and serine enzyme activities in developing culex pipiens resistance against carbaryl (Sevin), malathion and bacillus Thurengiensis serovar H-14

In Egypt, chemical insecticides are used repeatedly in mosquito control programs leading to increase insect resistance in the field especially against carbamate, Organophosphates and Pyrethroids, B.t.i. strains are restrictly used. In order to find a quick method for detecting elevation of resistance to the old insecticides or newly used biological insecticides, our research correlated between level of detoxifying and serine enzyme activity with elevation of resistance in Culex pipiens larvae against carbamate, DP and biological insecticides. Results proved that α and β-esterases showed decrease during early formation of resistance when using both carbamate and OP insecticides while no great change in B.t.i. resistant generations. Glutathione S- transferase showed positive significant difference between susceptible and carbamate and OP and B.t.i. resistance populations. Serine protease were good indicators for measuring OP and B.t.i. resistance elevation.